Overactive bladder (OAB) is a problem with bladder-storage function that causes a sudden urge to urinate. The urge may be difficult to stop, and overactive bladder may lead to the involuntary loss of urine (incontinence). Symptoms include: a sudden urge to urinate that's difficult to control, incontinence, frequent urination, and nocturia. The first line of treatments for OAB involves changes in diet, weight control, bladder training and pelvic floor exercises, and medications. If the first line treatments are not effective, then bladder injections, nerve stimulation, and surgery are then considered.
Sacral nerve stimulation is one of the more common stimulation therapies used today to treat OAB. There is only one device that has FDA approval being used today, InterStim™ Therapy developed by Medtronic. InterStim™ is a neuromodulation technique that targets the sacral nerves near the tailbone. These nerves play a role in controlling certain bladder muscles and functions. The therapy involves modulating these nerves, usually the third sacral nerve, through electrical impulses in order to help the brain and nerves communicate properly. This treatment is a two-step process starting with an evaluation process, and then an implantation process if the patient is deemed suitable for the procedure. For the evaluation, the doctor either inserts a temporary thin lead wire near the sacral nerves or a long-term lead that is fully implanted. The lead is connected to an external neurostimulator which generates mild electrical pulses. If the patient passes the evaluation, the doctor typically implants an implantable pulse generator (IPG) in a deep subcutaneous pocket in the right buttock connected to the lead and thus to the sacral nerves.
Currently, about 60% to 80% of patients undergoing sacral nerve stimulation are successful in bladder function improvement. Furthermore, a successful improvement only means a person who has had at least a 50% improvement with OAB. One objective of the present disclosure is to increase the efficacy of idiopathic overactive bladder treatments through nerve stimulation.